Hundreds of thousands of Americans die yearly due to cancers. A disease that appears in such large numbers in the human species is rare to be found in the elephant species. The article Elephants Revived a "Zombie" Gene that May Fend Off Cancer talks about how these low rates of cancer found in elephants may be due to a "zombie gene". It is a defunct duplicate of the LIF gene that was brought about in evolution. When there is damage to any DNA in an elephant, the elephants' cells will increase the activity of the zombie gene, LIF6, destroying the cell completely. Researches declare that this destroys any genetic defects that are caused by cancer. The LIF gene has numerous functions in mammals. In elephants, the LIF gene is duplicated several times as pseudogenes. These genes do not have the correct sequence to produce functioning transcripts. Researchers question whether these duplications may have an affect on the elephants' cell response to any DNA damage, which is completely destroying it.
The team of researches found that the LIF6 gene, one of the duplicated pseudogenes, had duplicated in a way that it produces a transcript. That specific gene product is controlled by TP53 which is a tumor suppressor. The TP53 protein regulates cell division and keeps the cell from dividing and growing at too quick of a rate or in an uncontrolled way. The over expression of LIF6 in the cells of elephants cause the cells to undergo apoptosis, causing the death of the cell. Researchers then had the idea to introduce the gene into the ovary of a Chinese hamster. When they did, the results showed that the gene had the same response to any DNA damage, complete destruction. There is still more work to be done to confirm the relationship between the LIF6 gene and low rates of cancer. This is definitely an interesting genetic discovery and could lead to many interesting findings in future research.